Open AccessEvaluation of the Epidemiological Relevance of Variable-Number Tandem-Repeat Genotyping of Mycobacterium bovis and Comparison of the Method with IS 6110 Restriction Fragment Length Polymorphism Analysis and Spoligotyping
Author(s) -
Caroline Allix,
Karl Walravens,
Claude Saegerman,
Jacques Godfroid,
Philip Supply,
Maryse Fauville-Dufaux
Publication year - 2006
Publication title -
journal of clinical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.349
H-Index - 255
eISSN - 1070-633X
pISSN - 0095-1137
DOI - 10.1128/jcm.01775-05
Subject(s) - genotyping , variable number tandem repeat , restriction fragment length polymorphism , mycobacterium bovis , tandem repeat , biology , genetics , dna profiling , genotype , dna , mycobacterium tuberculosis , medicine , tuberculosis , gene , genome , pathology
Sources ofMycobacterium bovis contamination remain unclear for many cases of animal and human disease. A major limitation is the lack of sufficiently informative or epidemiologically well evaluated molecular methods for typing. Here, we report an evaluation of a high-throughput method based on 29 mycobacterial interspersed repetitive unit-variable-number tandem-repeat (MIRU-VNTR) loci to genotype 127M. bovis isolates from cattle from 77 different Belgian farms, representative of a nationwide collection obtained from 1995 to 2003. MIRU-VNTR stability was demonstrated by analyzing a series of 74 isolates in total, obtained from different animals from a single farm or from different farms with an identified epidemiological link. The genotyping results and the genotypic diversity (h ) were compared with those obtained by IS6110 restriction fragment length polymorphism (RFLP) analysis and spoligotyping. Among 68 isolates with no known epidemiological link, MIRU-VNTR typing discriminated better than either RFLP analysis or spoligotyping, with isolates taken individually (32 versus 16 and 17 genotypes;h = 0.91 versus 0.73 and 0.85, respectively) or in combination (32 versus 28 genotypes;h = 0.91 versus 0.92). Maximal resolution was already achieved with a subset of 9 loci. The observed congruence of the genetic relationships based on IS6110 RFLP analysis, spoligotyping, and MIRU-VNTR markers is consistent with a clonal population structure ofM. bovis. These results support MIRU-VNTR typing as a convenient and discriminatory technique for analysis of the population structure ofM. bovis in much greater detail and for addressing some still unresolved issues in the epidemiology of the pathogen.